notch top ECU pinout wiring - Zilvia.net Forums | Nissan 240SX (Silvia) and Z (Fairlady) Car Forum

s14SRguy · 08-05-2013, 10:23 AM

I've searched and tried numerous things, but something here is sending me in circles.

I have a SR20DET s14 Notch Top motor in a 1995 s14 running a WC RED ECU

For some reason, there's a problem with power going into my MAF.

using the FSM, i tried to check continuity, however i ran into the following problems.

according to this guide (SR ECU PINOUTS : SR20DET Forum (rear-drive)) it states the following for a notch top:

26 B Mass Air Flow Sensor Ground
27 W Mass Air Flow Sensor

FSM says same thing. FSM also shows the pinout for mine (nicoclub thread doesnt show it)

Now what confuses me, I don't have a wire going into pinout 26, nor do i see a metal prong in there, so i dont see how i can test that. Is it possible for the grounds to be re-grounded elsewhere? It appears the maf cables go up into the main harness and dissappear into it, so i cant really trace the maf wires themselves once they merge into the rest of the harness

I checked power between MAF terminal D and terminal 27 and there was no continuity. I tried to splice and run a new wire from the maf terminal D to right before pinout 27 and the car starts a bit better but bogs worse under throttle.

Maybe it will help to mention when i unplug the maf, the car stays on and almost idles a little better, when i plug it in i can hold it halfway plugged in and it starts to bog hard and will start to die. if i push it in the rest of the way it stops dying and goes back to a rough idle.

so main questions...
Does anyone know a reason why theres no pinout in 26? is my plug just fucked up or is there a chance the ground was moved to a different location? or is it a different pinout?

Is it possibly the ECU giving bad signals?

if it is a bad wire, is there any reason the car wouldnt start with the wire from D to 27 replaced? i.e. am i missing a relay or something? wiring diagram in FSM shows its a straight connection.

This has been driving me crazy, and search isn't bringing up anything i havent already read a million times over, If anyone has knowledge on this and can help out that would be great, thanks.

DISREGARD

found out, after looking all around the internet from some foreign website, the pinout is read from harness side. not ECU plugin side.

was hooking up maf to the iacv/acc, causing the rough idle

found proper wires, checked with meter, as per FSM. MAF was internally shorted.

New maf on the way.

08-05-2013, 10:23 AM	#1
s14SRguy Leaky Injector Join Date: Jul 2012 Location: riverside Posts: 132 Trader Rating: (2) Feedback Score: 2 reviews	notch top ECU pinout wiring I've searched and tried numerous things, but something here is sending me in circles. I have a SR20DET s14 Notch Top motor in a 1995 s14 running a WC RED ECU For some reason, there's a problem with power going into my MAF. using the FSM, i tried to check continuity, however i ran into the following problems. according to this guide (SR ECU PINOUTS : SR20DET Forum (rear-drive)) it states the following for a notch top: 26 B Mass Air Flow Sensor Ground 27 W Mass Air Flow Sensor FSM says same thing. FSM also shows the pinout for mine (nicoclub thread doesnt show it) Now what confuses me, I don't have a wire going into pinout 26, nor do i see a metal prong in there, so i dont see how i can test that. Is it possible for the grounds to be re-grounded elsewhere? It appears the maf cables go up into the main harness and dissappear into it, so i cant really trace the maf wires themselves once they merge into the rest of the harness I checked power between MAF terminal D and terminal 27 and there was no continuity. I tried to splice and run a new wire from the maf terminal D to right before pinout 27 and the car starts a bit better but bogs worse under throttle. Maybe it will help to mention when i unplug the maf, the car stays on and almost idles a little better, when i plug it in i can hold it halfway plugged in and it starts to bog hard and will start to die. if i push it in the rest of the way it stops dying and goes back to a rough idle. so main questions... Does anyone know a reason why theres no pinout in 26? is my plug just fucked up or is there a chance the ground was moved to a different location? or is it a different pinout? Is it possibly the ECU giving bad signals? if it is a bad wire, is there any reason the car wouldnt start with the wire from D to 27 replaced? i.e. am i missing a relay or something? wiring diagram in FSM shows its a straight connection. This has been driving me crazy, and search isn't bringing up anything i havent already read a million times over, If anyone has knowledge on this and can help out that would be great, thanks. DISREGARD found out, after looking all around the internet from some foreign website, the pinout is read from harness side. not ECU plugin side. was hooking up maf to the iacv/acc, causing the rough idle found proper wires, checked with meter, as per FSM. MAF was internally shorted. New maf on the way. Last edited by s14SRguy; 08-08-2013 at 09:10 PM.. Reason: updated incase im not the only one.